If the earth were to suddenly contract to `1/nth` of its present size without any change in its mass, the duration of the new day will be nearly

Options

A. 24/n hours
B. 24 n hours
C. `24//n^(2)` hours
D. `24n^(2)` hours

Answer

C

Explanation

Using principle of conservation of angular momentum,
`I_(1)omega_(1)=I_(2)omega_(2)`
`2/5MR^(2)xx(2pi)/24=2/5M(R/n)^(2)xx(2pi)/TrArrT=24/(n^(2))` hour